Field
Mitigation of wake turbulence through the weakening of wake vortices generated at outboard edges of aircraft wings, or outboard and/or inboard edges of ailerons, flaps, or other airfoils.
Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
The persistence of a vortex trailing behind a lifting airfoil such as a wing, is dependent not only upon vortex strength, but also upon how well a core of the vortex is defined. Vortex strength is governed by lift, which depends upon area and pressure differences between upper and lower airfoil surfaces. The core is well-defined if the airfoil is thin and if there is a high pressure difference between the upper and lower surfaces near a tip of the airfoil. This allows a streamline to roll around the outboard edge or tip of a wing or the inboard and/or outboard edges or tips of a flap, aileron, or other airfoil, from the high pressure region to the low pressure region along a very short distance. This results in a highly curved, fast moving streamline in a well-defined vortex core, which can persist for a long time downstream of the airfoil. The formation of a well-defined vortex core may be impeded by lengthening the distance traveled by the streamlines rolling from the high pressure region feature such as extra thickness, a non-lifting wing-tip extension, or a device such as a winglet. Such devices are designed to have lift characteristics that compensate for their own weight. They also tend to add drag, although they are designed to add as little as possible. The purpose of such features is to prevent the lifting vortex from forming a well-defined core, thereby allowing the vortex to dissipate quickly.